Electrical therapy has long been used in medicine to treat pain and other conditions. For example, transcutaneous electrical nerve stimulation (TENS) systems deliver electrical energy through electrode patches placed on the surface of a patient's skin to treat pam in tissue beneath and around the location of the patches. However, the TENS systems may not adequately alleviate pain in certain circumstances.
More recently, a technique in which electrodes are placed through the patient's skin into the target tissue has been proposed. Percutaneous Neuromodulation Therapy (“PNT”) (also sometimes called Percutaneous Electrical Nerve Stimulation or “PENS”) using percutaneously placed electrodes achieves significantly better pain relief results than TENS treatments using skin surface electrodes. This therapy is described in Ghoname et al., “Percutaneous Electrical Nerve Stimulation for Low Back Pain,” JAMA 281:818-23 (1999); Ghoname et al., “The Effect of Stimulus Frequency on the Analgesic Response to Percutaneous Electrical Nerve Stimulation in Patients with Chronic Low Back Pain,” Anesth. Analg. 88:841-6 (1999); Ahmed et al., “Percutaneous Electrical Nerve Stimulation (PENS): A Complementary Therapy for the Management of Pain Secondary to Bony Metastasis,” Clinical Journal of Pain 14:320-3 (1998); and Ahmed et al., “Percutaneous Electrical Nerve Stimulation: An Alternative to Antiviral Drugs for Herpes Zoster,” Anesth. Analg. 87:911-4 (1998). The contents of these references are incorporated herein by reference.
Thus far, PNT practitioners have used percutaneously placed acupuncture needles attached to waveform generators via cables and alligator clips to deliver the therapy to the patient. One feature of conventional PNT systems is that they typically include a number of electrical cables that must be properly connected to the corresponding percutaneous electrodes to deliver effective electrical therapy. Accordingly, a drawback with these conventional systems is that it can be difficult (particularly for inexperienced practitioners) to connect each electrical cable to the proper corresponding electrode. This drawback is shared as well by other systems that require multiple connections to the patient. Such systems include electrical monitoring systems and drug delivery systems.